{"api_version":"1","generated_at":"2026-04-22T23:31:16+00:00","cve":"CVE-2021-38496","urls":{"html":"https://cve.report/CVE-2021-38496","api":"https://cve.report/api/cve/CVE-2021-38496.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2021-38496","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-38496"},"summary":{"title":"CVE-2021-38496","description":"During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.","state":"PUBLIC","assigner":"security@mozilla.org","published_at":"2021-11-03 01:15:00","updated_at":"2022-03-17 19:20:00"},"problem_types":["CWE-416"],"metrics":[],"references":[{"url":"https://www.mozilla.org/security/advisories/mfsa2021-44/","name":"https://www.mozilla.org/security/advisories/mfsa2021-44/","refsource":"MISC","tags":[],"title":"Security Vulnerabilities fixed in Firefox ESR 78.15 — Mozilla","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-45/","name":"https://www.mozilla.org/security/advisories/mfsa2021-45/","refsource":"MISC","tags":[],"title":"Security Vulnerabilities fixed in Firefox ESR 91.2 — Mozilla","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-43/","name":"https://www.mozilla.org/security/advisories/mfsa2021-43/","refsource":"MISC","tags":[],"title":"Security Vulnerabilities fixed in Firefox 93 — Mozilla","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-46/","name":"https://www.mozilla.org/security/advisories/mfsa2021-46/","refsource":"MISC","tags":[],"title":"404: Page Not Found","mime":"text/html","httpstatus":"404","archivestatus":"404"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-47/","name":"https://www.mozilla.org/security/advisories/mfsa2021-47/","refsource":"MISC","tags":[],"title":"Security Vulnerabilities fixed in Thunderbird 91.2 — Mozilla","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1725335","name":"https://bugzilla.mozilla.org/show_bug.cgi?id=1725335","refsource":"MISC","tags":[],"title":"Access Denied","mime":"text/html","httpstatus":"200","archivestatus":"200"},{"url":"https://www.debian.org/security/2022/dsa-5034","name":"DSA-5034","refsource":"DEBIAN","tags":[],"title":"Debian -- Security Information -- DSA-5034-1 thunderbird","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html","name":"[debian-lts-announce] 20220104 [SECURITY] [DLA 2874-1] thunderbird security update","refsource":"MLIST","tags":[],"title":"[SECURITY] [DLA 2874-1] thunderbird security update","mime":"text/html","httpstatus":"200","archivestatus":"404"},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-38496","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-38496","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[{"cve_year":"2021","cve_id":"38496","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"debian","cpe5":"debian_linux","cpe6":"10.0","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"38496","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"debian","cpe5":"debian_linux","cpe6":"11.0","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"38496","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"o","cpe4":"debian","cpe5":"debian_linux","cpe6":"9.0","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"38496","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"mozilla","cpe5":"firefox","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"38496","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"mozilla","cpe5":"firefox_esr","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"},{"cve_year":"2021","cve_id":"38496","vulnerable":"1","versionEndIncluding":"","cpe1":"cpe","cpe2":"2.3","cpe3":"a","cpe4":"mozilla","cpe5":"thunderbird","cpe6":"*","cpe7":"*","cpe8":"*","cpe9":"*","cpe10":"*","cpe11":"*","cpe12":"*","cpe13":"*"}],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[{"cve":"CVE-2021-38496","qid":"159412","title":"Oracle Enterprise Linux Security Update for firefox (ELSA-2021-3755)"},{"cve":"CVE-2021-38496","qid":"159428","title":"Oracle Enterprise Linux Security Update for firefox (ELSA-2021-3791)"},{"cve":"CVE-2021-38496","qid":"159429","title":"Oracle Enterprise Linux Security Update for thunderbird (ELSA-2021-3838)"},{"cve":"CVE-2021-38496","qid":"159430","title":"Oracle Enterprise Linux Security Update for thunderbird (ELSA-2021-3841)"},{"cve":"CVE-2021-38496","qid":"178822","title":"Debian Security Update for firefox-esr (DSA 4981-1)"},{"cve":"CVE-2021-38496","qid":"178831","title":"Debian Security Update for firefox-esr (DLA 2782-1)"},{"cve":"CVE-2021-38496","qid":"178983","title":"Debian Security Update for thunderbird (DSA 5034-1)"},{"cve":"CVE-2021-38496","qid":"178986","title":"Debian Security Update for thunderbird (DLA 2874-1)"},{"cve":"CVE-2021-38496","qid":"183251","title":"Debian Security Update for firefox-esrthunderbird (CVE-2021-38496)"},{"cve":"CVE-2021-38496","qid":"198534","title":"Ubuntu Security Notification for Firefox Vulnerabilities (USN-5107-1)"},{"cve":"CVE-2021-38496","qid":"198559","title":"Ubuntu Security Notification for Thunderbird Vulnerabilities (USN-5132-1)"},{"cve":"CVE-2021-38496","qid":"198641","title":"Ubuntu Security Notification for Thunderbird Vulnerabilities (USN-5248-1)"},{"cve":"CVE-2021-38496","qid":"239664","title":"Red Hat Update for firefox (RHSA-2021:3757)"},{"cve":"CVE-2021-38496","qid":"239665","title":"Red Hat Update for firefox (RHSA-2021:3756)"},{"cve":"CVE-2021-38496","qid":"239666","title":"Red Hat Update for firefox (RHSA-2021:3755)"},{"cve":"CVE-2021-38496","qid":"239677","title":"Red Hat Update for firefox (RHSA-2021:3791)"},{"cve":"CVE-2021-38496","qid":"239682","title":"Red Hat Update for thunderbird (RHSA-2021:3841)"},{"cve":"CVE-2021-38496","qid":"239683","title":"Red Hat Update for thunderbird (RHSA-2021:3840)"},{"cve":"CVE-2021-38496","qid":"239684","title":"Red Hat Update for thunderbird (RHSA-2021:3839)"},{"cve":"CVE-2021-38496","qid":"239685","title":"Red Hat Update for thunderbird (RHSA-2021:3838)"},{"cve":"CVE-2021-38496","qid":"257116","title":"CentOS Security Update for firefox (CESA-2021:3791)"},{"cve":"CVE-2021-38496","qid":"257126","title":"CentOS Security Update for thunderbird (CESA-2021:3841)"},{"cve":"CVE-2021-38496","qid":"296066","title":"Oracle Solaris 11.4 Support Repository Update (SRU) 40.107.3 Missing (CPUOCT2021)"},{"cve":"CVE-2021-38496","qid":"353982","title":"Amazon Linux Security Advisory for thunderbird : ALAS2-2022-1818"},{"cve":"CVE-2021-38496","qid":"375940","title":"Mozilla Firefox ESR Multiple Vulnerabilities (MFSA2021-44)"},{"cve":"CVE-2021-38496","qid":"375943","title":"Mozilla Firefox ESR Multiple Vulnerabilities (MFSA2021-45)"},{"cve":"CVE-2021-38496","qid":"375945","title":"Mozilla Firefox Multiple Vulnerabilities (MFSA2021-43)"},{"cve":"CVE-2021-38496","qid":"375958","title":"Mozilla Thunderbird Multiple Vulnerabilities (MFSA2021-46)"},{"cve":"CVE-2021-38496","qid":"375959","title":"Mozilla Thunderbird Multiple Vulnerabilities (MFSA2021-47)"},{"cve":"CVE-2021-38496","qid":"501553","title":"Alpine Linux Security Update for firefox-esr"},{"cve":"CVE-2021-38496","qid":"502069","title":"Alpine Linux Security Update for firefox-esr"},{"cve":"CVE-2021-38496","qid":"502081","title":"Alpine Linux Security Update for firefox"},{"cve":"CVE-2021-38496","qid":"502381","title":"Alpine Linux Security Update for thunderbird"},{"cve":"CVE-2021-38496","qid":"503632","title":"Alpine Linux Security Update for thunderbird"},{"cve":"CVE-2021-38496","qid":"503634","title":"Alpine Linux Security Update for thunderbird"},{"cve":"CVE-2021-38496","qid":"503650","title":"Alpine Linux Security Update for thunderbird"},{"cve":"CVE-2021-38496","qid":"503669","title":"Alpine Linux Security Update for thunderbird"},{"cve":"CVE-2021-38496","qid":"503852","title":"Alpine Linux Security Update for firefox"},{"cve":"CVE-2021-38496","qid":"504812","title":"Alpine Linux Security Update for firefox-esr"},{"cve":"CVE-2021-38496","qid":"506260","title":"Alpine Linux Security Update for thunderbird"},{"cve":"CVE-2021-38496","qid":"751210","title":"SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2021:3331-1)"},{"cve":"CVE-2021-38496","qid":"751226","title":"OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:3331-1)"},{"cve":"CVE-2021-38496","qid":"751230","title":"SUSE Enterprise Linux Security Update for MozillaFirefox (SUSE-SU-2021:3446-1)"},{"cve":"CVE-2021-38496","qid":"751237","title":"OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:3451-1)"},{"cve":"CVE-2021-38496","qid":"751246","title":"OpenSUSE Security Update for MozillaFirefox (openSUSE-SU-2021:1367-1)"},{"cve":"CVE-2021-38496","qid":"751542","title":"OpenSUSE Security Update for MozillaThunderbird (openSUSE-SU-2021:4150-1)"},{"cve":"CVE-2021-38496","qid":"751566","title":"OpenSUSE Security Update for MozillaThunderbird (openSUSE-SU-2021:1635-1)"},{"cve":"CVE-2021-38496","qid":"940182","title":"AlmaLinux Security Update for firefox (ALSA-2021:3755)"},{"cve":"CVE-2021-38496","qid":"940268","title":"AlmaLinux Security Update for thunderbird (ALSA-2021:3838)"},{"cve":"CVE-2021-38496","qid":"960080","title":"Rocky Linux Security Update for firefox (RLSA-2021:3755)"}]},"source_records":{"cve_program":{"data_type":"CVE","data_format":"MITRE","data_version":"4.0","CVE_data_meta":{"ID":"CVE-2021-38496","ASSIGNER":"security@mozilla.org","STATE":"PUBLIC"},"affects":{"vendor":{"vendor_data":[{"vendor_name":"Mozilla","product":{"product_data":[{"product_name":"Thunderbird","version":{"version_data":[{"version_value":"78.15","version_affected":"<"},{"version_value":"91.2","version_affected":"<"}]}},{"product_name":"Firefox ESR","version":{"version_data":[{"version_value":"91.2","version_affected":"<"},{"version_value":"78.15","version_affected":"<"}]}},{"product_name":"Firefox","version":{"version_data":[{"version_value":"93","version_affected":"<"}]}}]}}]}},"problemtype":{"problemtype_data":[{"description":[{"lang":"eng","value":"Use-after-free in MessageTask"}]}]},"references":{"reference_data":[{"url":"https://www.mozilla.org/security/advisories/mfsa2021-47/","refsource":"MISC","name":"https://www.mozilla.org/security/advisories/mfsa2021-47/"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-45/","refsource":"MISC","name":"https://www.mozilla.org/security/advisories/mfsa2021-45/"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-43/","refsource":"MISC","name":"https://www.mozilla.org/security/advisories/mfsa2021-43/"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-46/","refsource":"MISC","name":"https://www.mozilla.org/security/advisories/mfsa2021-46/"},{"url":"https://www.mozilla.org/security/advisories/mfsa2021-44/","refsource":"MISC","name":"https://www.mozilla.org/security/advisories/mfsa2021-44/"},{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1725335","refsource":"MISC","name":"https://bugzilla.mozilla.org/show_bug.cgi?id=1725335"},{"refsource":"DEBIAN","name":"DSA-5034","url":"https://www.debian.org/security/2022/dsa-5034"},{"refsource":"MLIST","name":"[debian-lts-announce] 20220104 [SECURITY] [DLA 2874-1] thunderbird security update","url":"https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html"}]},"description":{"description_data":[{"lang":"eng","value":"During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93."}]}},"nvd":{"publishedDate":"2021-11-03 01:15:00","lastModifiedDate":"2022-03-17 19:20:00","problem_types":["CWE-416"],"metrics":{"baseMetricV3":{"cvssV3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH","baseScore":8.8,"baseSeverity":"HIGH"},"exploitabilityScore":2.8,"impactScore":5.9},"baseMetricV2":{"cvssV2":{"version":"2.0","vectorString":"AV:N/AC:M/Au:N/C:P/I:P/A:P","accessVector":"NETWORK","accessComplexity":"MEDIUM","authentication":"NONE","confidentialityImpact":"PARTIAL","integrityImpact":"PARTIAL","availabilityImpact":"PARTIAL","baseScore":6.8},"severity":"MEDIUM","exploitabilityScore":8.6,"impactScore":6.4,"acInsufInfo":false,"obtainAllPrivilege":false,"obtainUserPrivilege":false,"obtainOtherPrivilege":false,"userInteractionRequired":true}},"configurations":{"CVE_data_version":"4.0","nodes":[{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*","versionEndExcluding":"93.0","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*","versionStartIncluding":"91.0","versionEndExcluding":"91.2","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*","versionEndExcluding":"78.15","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*","versionStartIncluding":"91.0","versionEndExcluding":"91.2","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*","versionEndExcluding":"78.15","cpe_name":[]}]},{"operator":"OR","children":[],"cpe_match":[{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*","cpe_name":[]},{"vulnerable":true,"cpe23Uri":"cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*","cpe_name":[]}]}]}},"legacy_mitre":{"record":{"CveYear":"2021","CveId":"38496","Ordinal":"214158","Title":"CVE-2021-38496","CVE":"CVE-2021-38496","Year":"2021"},"notes":[{"CveYear":"2021","CveId":"38496","Ordinal":"1","NoteData":"During operations on MessageTasks, a task may have been removed while it was still scheduled, resulting in memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 78.15, Thunderbird < 91.2, Firefox ESR < 91.2, Firefox ESR < 78.15, and Firefox < 93.","Type":"Description","Title":null},{"CveYear":"2021","CveId":"38496","Ordinal":"2","NoteData":"2021-11-02","Type":"Other","Title":"Published"},{"CveYear":"2021","CveId":"38496","Ordinal":"3","NoteData":"2022-01-04","Type":"Other","Title":"Modified"}]}}}